Please draw the mind map of chapter is matter around us pure ?
Answers
Answer:
Anything which has mass and occupies space is called matter. It may be solid, liquid or gas.
Matter is of 2 types -
1. Pure Matter
2. Impure substances
Pure Matter
Pure substances may be defined as material which contains only one kind of atoms or molecules.
Pure substances are of 2 kinds : -
Elements -
Pure substances which are made up of only one kind of atoms are known as elements. All atoms in an element are identical. Atoms of different elements are different.
Compounds -
Pure substances which are made up of only one kind of molecules are known as compounds. Atoms constituting are from two or more different elements. The different elements are combined in fixed proportion in a compound.
Impure Matter
Impure matters are also called mixture. A mixture is a material which contains two or more different kinds of particles (atoms or molecules) which do not react chemically but are physically mixed together in any proportion.
Mixtures are of 2 types:
Homogeneous mixtures -
A mixture is said to be homogeneous if all the components of the mixture are uniformly mixed and there are no boundaries of separation between them. For example- Salt in water etc.
Heterogeneous mixtures -
A mixture is sad to be heterogeneous if all the components of the mixture are not thoroughly mixed and there are visible boundaries of separation between them. For example- Sand in water etc.
Before we proceed further we should know the difference between the properties of compounds and mixtures.
Properties of Compounds -
1. A compound is a homogeneous substance.
2. A compound has a definite composition.
3. A compound has definite melting point or boiling point.
4. Energy is absorbed or evolved in the form of heat or light during the formation of a compound.
5. The properties of compound are entirely different from those of its constituents.
For example – If we mix Iron and Sulphur in a watch glass, we get a mixture. This is then heated till a black mass is formed. This leads to formation of compound called Iron Sulphide.
On bringing magnet near to it, no Iron is attracted towards it. Also, Sulphur does not dissolve on adding carbon disulphide, thus, not showing the properties of its constituents.
6. The constituents of a compound cannot be separated by simple physical means.